A garden is a lot of things - food for humans, but not only for humans. 

Spiders like some "pest" insects, e.g. pill bugs (eat seedlings), ear wigs (eat lettuce, artichoke, beans).  Our least favorite insects this past summer were the tree hoppers - plant suckers with scary looking nymphs (that would scare away most predators).  The tree hoppers destroyed our incredibly eggplant plants ("Millionaire").  We were sorry to see them go down - made new eggplants for months.

And last week, I found fresh new mushrooms.  It's a look-alike for the deadly Amanita ocreata.  Look-alike is not same as.  These in the garden were perfectly safe - and edible.  Volvopluteus gloiocephala - pretty with pink spores.  I took them to show my beginners' mushroom identification class last night.